Rapt Therapeutics announces publication of Phase 1a/1n trial of zelnecirnon

RAPT Therapeutics announced that results from its previously disclosed Phase 1a/1b clinical trial of zelnecirnon were published in Allergy. The Phase 1a portion of the trial was a standard single and multiple dose-escalation study in 72 healthy volunteers. The Phase 1b portion of the trial was a randomized, double-blind, placebo-controlled study examining zelnecirnon as monotherapy in 31 patients with moderate-to-severe atopic dermatitis. The findings showed that once-daily zelnecirnon treatment was generally well tolerated, with no serious adverse events reported, and all reported treatment-emergent adverse events were mild-to-moderate in nature across both patients with atopic dermatitis and healthy volunteers. In the Phase 1b trial, after four weeks of treatment, patients with moderate-to-severe AD who received zelnecirnon showed a 36.3% change from baseline in the Eczema Area and Severity Index score, a standard measure of disease severity, compared to 17.0% in the placebo group. Notably, in the two-week period following the end of treatment, the zelnecirnon group showed continued deepening of the response and a statistically significant difference compared to placebo with a 53.2% change from baseline in EASI at the six-week time point compared to 9.6% in the placebo group. Key Findings from the Phase 1b Study in Patients with Atopic Dermatitis: In the Phase 1b study, 21 patients with moderate-to-severe atopic dermatitis were treated with 400 mg of zelnecirnon, administered orally once a day for four weeks, while 10 patients received placebo. The zelnecirnon group showed clear improvement in key efficacy measures compared to placebo at the end of the four-week treatment period, including percent change from baseline in the Eczema Area and Severity Index score, validated Investigator Global Assessment and pruritis Numerical Rating Scale: Patients treated with zelnecirnon achieved a 36.3% change from baseline in EASI score compared with 17.0% in patients in the placebo group; 42.9% of patients treated with zelnecirnon achieved a 50% change from baseline in EASI score compared with 10.0% in the placebo group; 4.8% of patients treated with zelnecirnon achieved a vIGA score of 0/1 and at least a two-point improvement over baseline compared with 0.0% in the placebo group; and 45.0% of patients treated with zelnecirnon achieved at least a four-point reduction in the pruritus NRS score, compared with 22.2% in the placebo group; Patients were also evaluated for exploratory endpoints at six weeks. At six weeks, the patients treated with zelnecirnon showed further deepening of the response in EASI score and vIGA: Patients treated with zelnecirnon achieved a 53.2% change from baseline in EASI score compared with 9.6% in patients in the placebo group; 61.9% of patients treated with zelnecirnon achieved EASI-50 compared with 20.0% in the placebo group; and 14.3% of patients treated with zelnecirnon achieved a vIGA score of 0/1 and at least a two-point improvement over baseline compared with 0.0% in the placebo group